MARS PATHFINDER MISSION STATUS
October 22, 1997
The Mars Pathfinder operations team is continuing its efforts to reestablish communications with the Pathfinder lander. Although they are experiencing communications difficulties, the team is confident that the spacecraft is still operating on the surface of Mars, according to Mission Manager Richard Cook. The last time they were able to send a command to the Pathfinder lander instructing it to transmit a signal back to Earth was on Sol 93, which was Tuesday, October 7, at 7:21 a.m. Pacific Daylight Time.
Team members suspect that the spacecraft may not be receiving commands from Earth properly because the lander's hardware has become much colder than normal. In regular operations, when the lander's transmitter is turned on, spacecraft hardware warms up sufficiently to operate normally. Since the transmitter has not been on for several days, engineers suspect that temperatures within the lander are considerably colder than normal. Predicted internal temperatures drop to as low as -50 C (-58 F) in the early morning and only rise to about -30 C (-22 F) in the late afternoon. These temperatures are about 20 C (38 F) colder than the coldest previous operational temperatures.
The lower temperatures cause the spacecraft radio hardware to operate outside the range of radio frequencies that ground controllers have used in the past. During the past three weeks the operations team has been transmitting to the spacecraft at a lower frequency and sweeping through a wider frequency range, a technique that has been used on other missions to attempt to cause the spacecraft receiver to lock on to the transmitted signal. Once ground controllers finish this, they send commands instructing the lander to turn on its transmitter and send a signal back to Earth.
To be certain that they investigate all possibilities, team members are also consulting with experts knowledgeable about the radio and other key elements of the spacecraft. They have identified some new scenarios that are being pursued to regain communications. These recommendations include doing more testing of the engineering model hardware in the laboratory to better understand how the spacecraft might be behaving. Another recommendation has suggested shifting and increasing the range of frequencies being swept through much more than previously attempted.
According to Project Manager Brian Muirhead, the possibility exists that an unrecoverable problem may have occurred. Team members expected that, once the lander's onboard battery died, cold and thermal cycling could result in a failure of some other element of Pathfinder and thereby end the mission. "However, the Pathfinder project is funded to continue operations until August 1998, and the team will continue to do everything possible to reestablish communications until all options have been exhausted," Muirhead said. The mission has already exceeded all of its goals in terms of spacecraft lifetime and data return.
The science team, meanwhile, continues to process and analyze the large volume of data sent back by Pathfinder's lander and rover. Further science products are planned and new results will continue to be presented as they develop.
The team will continue its daily uplink sessions with Mars Pathfinder. Daily audio updates are available by calling (800) 391-6654.
MARS PATHFINDER MISSION STATUS
21 October 1997, 8:30 a.m. PDT
At this time, the status of the Mars Pathfinder mission remains the same. We are attempting to regain communications with the lander, but have not seen a signal since October 7th. We have high confidence, however, that the spacecraft is still functioning, but the extreme cold temperatures of the lander is preventing communications. We are pursuing several courses of action which should allow us to recover and continue normal operations.
For further information on the Mars Pathfinder Mission, please call our Mission Status Report line at 1-800-391-6654.
Today we attempted to make contact with Pathfinder using the 70 meter station in Goldstone California. We commanded the spacecraft to turn on the auxiliary transmitter, but unfortunately we did not see any down link signal.
Due to commitments to the Galileo mission we moved our operations to the 34 meter antenna and commanded the spacecraft to turn on the SSPA transmitter. The SSPA is a backup transmitter in addition to our primary and auxiliary transmitters. Unfortunately, we did not receive any signal during this second attempt.
We will continue with our efforts to reestablish contact with Pathfinder and will promptly post any favorable developments.
For further information on the Mars Pathfinder Mission, please call our Mission Status Report line at 1-800-391-6654.
MARS PATHFINDER MISSION STATUS
16 October 1997, 4:00 p.m. PDT
After making some changes in our commanding strategy yesterday, commands were sent to the Sagan Memorial station which should have resulted in a signal from the spacecraft’s low gain antenna being received on Earth. The signal was expect at 1:15 this afternoon, but was not seen. The spacecraft was then commanded to send two additional signals to Earth today using both its primary and auxiliary transmitters, but neither signal was received. The last verified signal we received from Pathfinder was nine days ago on Sol 93. Tomorrow’s plans include the anticipated use of the 70 meter station at Goldstone California. Sol 103 will mark the first use of our new temperature models for both commanding the spacecraft and receiving a signal from the spacecraft over its auxiliary transmitter.
The spacecraft team remains optimistic that the Sagan memorial station is good health and that our current difficulties can be traced to lower than normal operating temperatures.
For further information on the Mars Pathfinder Mission, please call our Mission Status Report line at 1-800-391-6654.
MARS PATHFINDER MISSION STATUS
15 October 1997, 3:00 p.m. PDT
Today again we attempted to up link commands to the spacecraft that would turn on the transmitter, however, we were unsuccessful. Tomorrow we will resume our attempts to command the spacecraft. Our team is continuing to investigate the problem in an effort to better understand what is occurring on board the spacecraft.
For further information on the Mars Pathfinder Mission, please call our Mission Status Report line at 1-800-391-6654.
MARS PATHFINDER MISSION STATUS
13 October 1997, 1:15 p.m. PDT
Today we attempted to send a set of commands to the spacecraft to turn on its main transmitter. This is a similar set of commands that we have been sending for the past several days. We sent these commands over Deep Space Network station in Madrid. In both cases, we did not receive a transmitter on signal on the ground indicating the command has been received by the spacecraft. We also uplinked sequences that will start tomorrow morning when the spacecraft wakes up and turn on its transmitter near local solar noon. However, since we did not see the transmitter on today, we have no verification that these sequences were received by the spacecraft.
The Pathfinder anomoly team is continuing to investigate the problems we've had over the past several weeks, specifically related to commanding the spacecraft over the last week, and we are continuing to try to understand what configuration the spacecraft is in. We will have meetings tomorrow to discuss what our next step is in our strategy. We do plan to send sequences to the spacecraft that will attempt to move the high gain antenna and give us a downlink session in the middle of the day when we can actually receive telemetry data.
For further information on the Mars Pathfinder Mission, please call our Mission Status Report line at 1-800-391-6654.
MARS PATHFINDER MISSION STATUS
12 October 1997, 2:00 p.m. PDT
A spurious signal was apparently seen today from Mars Pathfinder, However when a second larger Deep Space Network antenna was brought on point, the signal was not observed. Tomorrow, we are hoping to see a 40 minute carrier-only signal from the spacecraft. The frequency range of the downlink sweep was increased to help better detect the signal from the Mars Pathfinder spacecraft.
For further information on the Mars Pathfinder Mission, please call our Mission Status Report line at 1-800-391-6654.